/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.spark.sql.execution.streaming

/**
 * A simple offset for sources that produce a single linear stream of data.
 */
case class LongOffset(offset: Long) extends Offset {

  override def compareTo(other: Offset): Int = other match {
    case l: LongOffset => offset.compareTo(l.offset)
    case _ =>
      throw new IllegalArgumentException(s"Invalid comparison of $getClass with ${other.getClass}")
  }

  def +(increment: Long): LongOffset = new LongOffset(offset + increment)
  def -(decrement: Long): LongOffset = new LongOffset(offset - decrement)

  override def toString: String = s"#$offset"
}
